Electrical connectors employing a plug-in contact spring



Aug. 23, 1966 J. BERNUTZ 3,268,350

ELECTRICAL CONNECTORS EMPLOYING A PLUG-IN CONTACT SPRING Filed Nov. 6,1964 4 Sheets-Sheet 1 Fg/E F/gJF Fig/6 Fig.2A 2 FIQZBJ F/QZC 5 t 250 :vw LL. F

Aug. 23, 1966 J. BERNUTZ 3,268,850

ELECTRICAL CONNECTORS EMPLOYING A PLUG-IN CONTACT SPRING Filed Nov. 6,1964 4 Sheets-$heet 2 Aug. 23, 1966 J. BERNUTZ ELECTRICAL CONNECTORSEMPLOYING A PLUG-IN CONTACT SPRING Filed Nov. 6, 1964 4 Sheets-Sheet 3J. BERNUTZ Aug. 23, 1966 ELECTRICAL CONNECTORS EMPLOYING A PLUG-INCONTACT SPRING Filed Nov. 6, 1964 4 Sheets-Sheet 4 Fig. 77

Fig.76

United States Patent 3,268,850 ELECTRICAL CONNECTORS EMPLOYING A PLUG-INCONTACT SPG Johannes Bernutz, Ludwigsburg-Hoheneck, Germany, as-

signor to International Standard Electric Corporation, New York, N.Y., acorporation of Delaware Filed Nov. 6, 1964, Ser. No. 409,520 Claimspriority, application Germany, Nov. 14, 1963, St 21,326 7 Claims. (Cl.339-217) The invention relates to electrical connectors and particularlyto a plug-in contact spring to be inserted into a spring strip housing.

It is an object of the invention to provide devices having contactsprings which may be used to connect leads in different ways, e.g. bysoldering, wrapping or crimping.

It is a further object of the invention to make allowances for theremoval of individual contact springs from the connecting end of aspring strip housing without the necessity of taking the housing apartor of disconnecting the leads connected to the contact spring.

It is yet another object of this invention to provide contact springswhich are adaptable for mass production and employ relatively few steps,while making proper contacts and holding dimensions to close tolerances.

These objects are achieved, according to the invention, by providing thecontact-making part with soldering lugs for use with diiierent types ofconnecting techniques such as soldering, wrapping crimping, or bywelding. In a preferred embodiment the contact spring embodies at leastone elastic stud which engages into corresponding recesses in thecontact strip housing after the contact spring has been inserted intothe housing from the connecting end, thereby securing the plug-incontact spring against shifting when a knife-blade is inserted orremoved from said contact strip, however, permitting removal of acontact spring from said strip housing in the direction of theconnecting end, after the stud has been disengaged. It is therebyachieved that the plug-in contact spring is provided in a simple way,besides for connection of leads by soldering of the conventional typealso for wrapping or crimping and that the contact spring can be removedfrom the housing at the connecting end without impairing the advantagesknown with this contact spring construction.

In a further embodiment of the invention the contactmaking portion ofthe contact spring is provided at the connecting end with two elasticstuds, which with their bent ends engage into corresponding recesses inthe housing, from which recesses they can be disengaged by means of aU-shaped extraction-tie for removing said contact spring.

A further embodiment of the invention provides that the tie is providedwith a center-stud showing a stud which presses in the plug-in directiontowards a protecting part of the spring strip housing.

In a further embodiment of the invention, said stud of the center-studis made elastic, or the center-stud of the tie is made elastic and isstud rigid.

Another embodiment of the invention is that said stud is T-shaped,elastically twisted and fixed to the tie, and that it engages in thetwisted position into recesses of the contact spring strip housing, orthat the stud has the shape of an L, also elastically twisted, fixed tothe tie, and that it engages into recesses of the housing in its twistedposition.

The accompanying drawings show examples of embodiments of the invention,wherein:

FIGS. 1A-1G show perspective views of a contact spring and sixdifiFerent connecting lugs;

3,268,850 Patented August .23, 1966 FIGS. 2A-2F show assemblages of theelements in FIGS. lA1G into ahousing;

FIGS. 3, 4 and 5 show a spring strip with several plugin contact springsfrom FIG. 1 as seen from the connecting end, in section from the side,and in section from the P;

FIGS. 6 and 7 show dilferent shapes of the tie or tieing device in twoelevations;

FIGS. 8 and 9 show a spring strip with contact springs and tiesaccording to FIG. 6 seen from the connecting end, and in section fromthe side;

FIG. 10 shows a contact spring provided with a tie of another shape;

FIGS. 11 and 12 show a partial view with a section through a contactspring strip with a contact spring according to FIG. 10;

FIG. 13 shows a partial view of a tie with another shape;

FIGS. 14 and 15 show a spring strip in elevation and section, thecontact springs of which are equipped with elastic studs at thecontact-making portion;

FIG. 16 shows a perspective view of a contact spring; and

FIG. 17 shows a tool to extract a contact spring according to FIG. 16from a spring strip as shown in FIGS. 14- and 15. v

The contact spring according to FIG. 1A consists of a contact-makingpart 1 which can be connected with different terminal lugs 2 to 7, shownin FIGS. lB-lG. This connection can be made by welding the two weldingpoints 16 of part 1. Part 1 encloses tie 11, shown more fully in FIG. 7,which is kept in place in part 1 by two grooves 17, as well as slots inthe ends of part 1. The tie 11 shows an elastic center-stud 13, providedwith a rigid stud 14.

When inserting a contact spring, according to FIG. 1A, into the springstrip housing 9, according to FIGS. 3, 4 and 5, from the connecting end,tab or tongue 8 of the stud 14 slides, with an elastic bending of thecenter stud 13 of the tie 11, along the oblique surface 18 of the fillet19 in the housing 9, and engages into the final position of the contactspring in said housing in recesses or receptacles 10 into which the tab8 inserts.

The contact spring is thereby fixed in the housing 9 at all sides with avery narrow play, because the contact-making part 1 of the contactspring is supported, when removing an inserted contact knife-blade,towards the housing side 20, thereby securing the contact spring alsoagainst shifting toward the contact knife-blade.

When the contact spring should be removed towards the connecting end theelastic center-stud 13 of the tie 11 is laterally pushed by means of apin-shaped tool 21 to such an extent that the tab 8 disengages fromreceptacles 10 and thereupon the contact spring can be removed.

In another type of construction according to FIG. 6 the tie 11 isprovided with a rigid center-stud 13, having an elastic stud 14. Thisstud engages with its tab 8, when inserting the contact spring into thehousing 9, according to FIGS. 8 and 9, behind the stud 15 on saidhousing. This type of contact spring is extracted from the housing inthe same way as described above, in that the elastic stud 14 isdisengaged by means of a pin-shaped tool 21, shown in FIG. 5, andthereupon the contact spring may be removed towards the terminal end.

Another construction type of the contact spring according to FIG. 10shows a tie 11, provided with a T-shaped stud 14. This stud engages,when inserting the contact spring into the housing 9, according to FIGS.11 and 12, into recesses or receptacles 10 in said housing, thussecuring the contact spring against shifting. When the contact springshould 'be removed from the contact strip housing 9 the elastic springstud 14 is turned back so that it disengages from the recesses orreceptacles 10 and the contact spring can be pulled 011 towards theterminal end.

According to another type of the tie 11, according to FIG. 13, thetension-spring stud 14 has the shape of an L, the effect, however, isthe same.

FIG. 16 shows another type of the contact spring. In this type thecontact-making part 1 is welded to the springs or studs 28 which servethe function of the studs 14. The springs 28 engage the recesses orreceptacles 10 of the housing 9 according to FIGS. 14 and 15, besidesbeing welded with the terminal lug 2, the bent ends 12 of said holdingsprings 28 secure the contact spring against shifting through engaginginto the recesses or receptacles 10.

When a contact spring shall be pulled off the housing 9, a fork-shapedtool, shown in FIG. 17, is plugged onto the contact spring. Thereby thetwo holding springs 28 are disengaged from the recesses 10 and thecontact spring can be pulled off towards the terminal end.

While the principles of the invention have been described above inconnection with specific apparatus and applications, it is to beunderstood that this description is made only by way of example and notas a limitation on the scope of the invention.

What is claimed. is:

1. An electrical connector, comprising:

a housing;

receptacles in said housing for receiving studs;

a plug-in contact spring to be inserted into said housing;

said spring including a contact-making part, slotted ends, and aterminal lug;

a fiat tie to control contact pressure, shaped to fit within said springand to lock into said slotted ends; means on said terminal lug forreceiving a suitable conductor;

said tie including an elastic stud to mate with said receptacles in saidhousing to hold the plug-in contact spring and tie in said housing;

said combination of housing, spring and tie forming a durable electricalconnector to receive suitable contact knife blades and to disengage fromsuch blades; and

said combination remaining easy to disassemble by disengaging said studand moving the contact spring in the direction of the terminal lug.

2. An electrical connector substantially as claimed in claim 1, inwhich:

said housing incorporates two recesses as receptacles for receivingstuds; said tie includes two elastic studs to mate with said tworecesses; and space is provided in said housing to permit a U-shapedextracting tool to be received in order to extract said spring bydisengaging the studs from the recesses. 3. An electrical connectorsubstantially as claimed in claim 1, in which:

the housing incorporates a projecting part as a receptacle for receivingand retaining studs; and the tie is provided with a center stud having astud portion to be held by said projecting part. 4. An electricalconnector substantially as claimed in claim 3,. in which:

the stud portion of the center stud is made elastic. 5. An electricalconnector substantially as claimed in claim 3, in which:

the center stud is composed of elastic material; and the stud portion ofthe center stud is composed of rigid material. 6. An electricalconnector substantially as claimed in claim 1, in which:

the stud is made T-shaped; and the receptacles in said housing arerecesses which the stud can engage when twisted. 7. An electricalconnector substantially as claimed in claim 1, in which:

the stud is L-shaped; and the receptacles in said housing are recesseswhich the stud can engage when twisted.

References Cited by the Examiner UNITED STATES PATENTS 3,069,652 12/1962Greco 339-176 3,079,5 82 2/ 1963 Lazar 339-217 FOREIGN PATENTS 1,214,0474/ 1960 France.

860,331 2/ 1961 Great Britain. 869,447 5/ 1961 Great Britain.

EDWARD C. ALLEN, Primary Examiner.

PATRICK A. CLIFFORD, Examiner.

1. AN ELECTRICAL CONNECTOR, COMPRISING: A HOUSING; RECEPTACLES IN SAIDHOUSING FOR RECEIVING STUDS; A PLUG-IN CONTACT SPRING TO BE INSERTEDINTO SAID HOUSING: SAID SPRING INCLUDING A CONTACT-MAKING PART, SLOTTEDENDS, AND A TERMINAL LUG; A FLAT TIE TO CONTROL CONTACT PRESSURE, SHAPEDTO FIT WITHIN SAID SPRING AND LOCK INTO SLOTTED ENDS; MEANS ON SAIDTERMINAL LUG FOR RECEIVING A SUITABLE CONDUCTOR; SAID TIE INCLUDING ANELASTIC STUD TO MATE WITH SAID RECEPTACLES IN SAID HOUSING TO HOLD THEPLUG-IN CONTACT SPRING AND TIE IN SAID HOUSING; SAID COMBINATION OFHOUSING, SPRING AND TIE FORMING A DURABLE ELECTRICAL CONNECTOR TORECEIVE SUITABLE CONTACT KNIFE BLADES AND TO DISENGAGED FROM SUCHBLADES; AND SAID COMBINATION REMAINING EASY TO DISASSEMBLE BYDISENGAGING SAID STUD AND REMOVING THE CONTACT SPRING IN THE DIRECTIONOF THE TERMINAL LUG